Search engines provide a powerful tool for locating content in documents in a large database of documents, such as the documents on the Internet or World Wide Web (WWW), or the documents stored on the computers of an Intranet. The documents are located using an index of documents in response to a search query, consisting of one or more words, terms, keywords and/or phrases, that is submitted by a user. The document index is generated by scanning the documents using one or more network crawlers (or web crawlers). When the number of documents to be indexed is large (e.g., billions of documents), accomplishing such scanning in a timely manner usually involves multiple crawlers operating in parallel.
During the scanning of documents by one or more crawlers, additional content or documents may be discovered based on links to such additional content or documents embedded in the documents that are scanned. One existing approach to providing links to additional content or documents is in the form of link tags. In hypertext documents, such link tags (sometimes called anchor tags) may include links to other documents or to other parts of the same document. Existing link tags, however, have several limitations. Notably, the information in existing link tags only conveys a document location. While link tags may also contain commands for displaying text when the user performs a “mouse over” over the link tag, for displaying text when the user performs a “mouse out” away from the link tag, for refreshing the browser display, or for returning the browser to a previous document location, none of these commands convey information about an identified document or other entity. In particular, existing link tags do not convey opinions, such as reviews and/or ratings of the content or documents at the locations identified in the link tags. Existing link tags are also unable to convey information about the relative importance of the locations identified in the link tags. Furthermore, the information in existing link tags is public. There is no mechanism to secure the information in a link tag such that it may only be viewed by a restricted audience. There is a need, therefore, for improved anchors for use by search engines.